The present invention relates to gas turbine driven power generators and, in particular, to techniques for regulating the reserve capacity of the electric power generator.
Utility companies and independent power producers (IPP) use gas turbines to generate electrical power. Gas turbines generate electrical power by turning generators. The power is distributed over power grids to customers who buy the power. The utilities and IPP are often required to hold in reserve a defined amount of their capacity to generate power.
For example, to participate in a system frequency regulation program, an IPP must hold in reserve a specific percentage of its power generation capacity. The reserve capacity is maintained so that the IPP is able to apply additional power from its reserve capacity when the grid frequency declines. The benefit to the IPP for participating in the frequency regulation program is that the IPP receives financial or other compensation from the connected utility. The requirement for a reserve capacity may also be imposed by contract, such as where the utility requires that its gas turbines operate at a part load capacity, for instance 95% of the total power capacity of the turbine.
To maintain a certain percentage of its power generation capacity in reserve, the IPP must know the total available capacity of its gas turbine on an ongoing basis. The available capacity of a gas turbine based power plant is highly dependent on the ambient conditions, e.g., temperature and barometric pressure, at the power plant. Other factors that affect the capacity of a gas turbine include the gas turbine's condition, e.g. cleanliness, of the compressor, turbine degradation, fuel type and quality. All of these factors are variable and difficult to reliably predict.